Fuel cell water purification system and method

Abstract

A water purification system includes a fuel cell stack, a steam generator, and a water purification unit. The fuel cell stack is adapted to provide heat to the steam generator and the steam generator is adapted to provide steam to the water purification unit.

1. A water purification system comprising:
 a fuel cell stack; 
 a steam generator; 
 a water purification unit; 
 an air exhaust stream conduit; and 
 a fuel exhaust stream conduit; 
 
       wherein:
 the air exhaust stream conduit and the fuel exhaust stream conduit are adapted to provide an air exhaust stream and a fuel exhaust stream, respectively, from the fuel cell stack to the steam generator to provide heat to convert inlet water of the steam generator into steam; and 
 the steam generator is adapted to provide the steam to the water purification unit. 
 
     
     
       2. The system of  claim 1 , wherein the water purification unit comprises a water desalination unit. 
     
     
       3. The system of  claim 1 , wherein the fuel cell stack is comprised of high temperature fuel cells. 
     
     
       4. The system of  claim 3 , wherein the fuel cells are solid oxide fuel cells. 
     
     
       5. The system of  claim 2 , wherein the fuel cell stack is electrically connected to water pumps of the water desalination unit. 
     
     
       6. The system of  claim 2 , wherein the water desalination unit comprises a vapor compression (VC), a multistage flash (MSF) or a multi effect distillation (MED) desalination unit. 
     
     
       7. A method of desalinating water comprising:
 generating electricity and air and fuel exhaust streams from a fuel cell stack; 
 providing the air exhaust stream which consists essentially of air into a steam generator to convert water in the steam generator into steam; and 
 heating salinated water with the steam from the steam generator during a desalination process to desalinate the salinated water. 
 
     
     
       8. The method of  claim 7 , further comprising providing electricity from the fuel cell stack to power a water desalination unit in which the salinated water is being desalinated. 
     
     
       9. The method of  claim 7 , wherein:
 the fuel cell stack comprises a solid oxide fuel cell stack; and 
 the desalination unit comprises a vapor compression (VC), a multistage flash (MSF) or a multi effect distillation (MED) desalination unit. 
 
     
     
       10. The system of  claim 1 , wherein the air exhaust stream conduit and the fuel exhaust stream conduit are arranged such that the air exhaust stream and the fuel exhaust stream are kept separate to sequentially heat the inlet water of the steam generator. 
     
     
       11. The system of  claim 1 , further comprising a splitter to split the steam generated by the steam generator to provide the steam to the water purification unit and to humidify a fuel inlet stream of the fuel cell stack. 
     
     
       12. The method of  claim 7 , further comprising providing the fuel exhaust stream into the steam generator to heat the water, wherein the air exhaust stream and the fuel exhaust stream are kept separate to sequentially heat the water in the steam generator. 
     
     
       13. The method of  claim 7 , further comprising splitting the steam from the steam generator to provide the steam to heat salinated water and to humidify a fuel inlet stream of the fuel cell stack.